Numerical analyses of stress and deformation in sandwich-structured composites

Abstract

Sandwich-structured composites are extensively used in aerospace, transportation, marine, and automotive applications where mechanical performance and weight-saving features are extremely critical. Consequently, analyzing the mechanical properties including the elastic behavior of the sandwich structure is incumbent for the precise application of such composites. This paper deals with the stress analysis of a two-dimensional (2-D) rectangular sandwich-structured composite with the help of a robust numerical model. A finite difference (FD) scheme based on the displacement potential function is developed to investigate the stress-strain behavior of the sandwich structure under different loading conditions. The 2-D mixed-boundary-value elastic problem is solved by implementing special FD formulations inside the domain and at the boundaries. The mathematical intricacy of the interfaces of the sandwich structure is handled by employing modified FD formula structures. Results obtained from the FD model show that the two interfacial regions constitute the critical stress zones, and the material having a higher modulus of elasticity experiences higher stress. The proposed FD model is validated by comparing the FD results for stress distribution and displacement fields with the results obtained from a commercial finite element (FE) package. The comparison between the FE and FD results shows a good agreement which constructively establishes the proposed FD scheme as an accurate and reliable technique for conducting the structural analysis.